Smoke and water tube boiler.



W. POLDERIVIAN, JR. & F. H. LUCHSINGER.

SMOKE AND WATER TUBE BolLER.

APPLICATION FILED APR. I2, 1915.

Patented Nov. 23, 1915.

/@Imwoeo WOUTER POLDERMAN, JR., AND FRIDOLIN HEINRICH 'LUCHSINGER, 0F

NETHERLANDS.

sans rar orrrcn.

Y'MUIDEN,

SMOKE AND WATER TUBE BOILEB..

Specication of Letters Patent.

Patented Nov. 23, 1915.

Application filed April 12,- 1915. Serial No. 20,941.

This invention relates to improvements` `in combined smokeand water-tube bo1lers,

in which the water spaces around the ordinary combustion chambers are dispensed with and water tubes are substituted for them, such tubes being arranged so as to eX- tend upwardly from a large transverse horizontal water pipe-connected to the bottom space of the boilerup to the water level, or steam chamber, above the tire tubes. These' water tubes'are also arranged close to one another in such a manner as to form a sub-` stantially solid and continuous wall or walls of water-tubes infclosingv the said combustion chamber or chambers and are curved slightly vertically. y

tioned watertubes enter the rear vertical plate of the boiler and inclose the combustion chamber at the top, in consequence of which they must be curved considerably and cannot be removed without destroying the bricking in of the combustion chamber.

Furthermore the horizontal or nearly hori' zontal portions of the water tubes 'caused by the tubes entering 4vthe rear plate as aforesaid, form an impediment'to the generation of steam in the tubes as they hinder the Vfree rising of the steam bubbles and finally they are very liable to be burntin consequence of the deposit of scale and the like. According to this invention these various objections are avoided by employing approximately vertical water tubes for -forming the rear Wall of the combustion chamber, said tubes enterin at their upper end a part of the top space o the boiler which overhangs the combustion chamber.- The bottom plate of this overhanging part is the crown plate of the combustion chamber and'has the sha e of a horizontal letter S one curve of w ich is connected to or forms a continuation of the nected to ororms a. continuation of the rear end plate of the overhanging part of the boiler. The first` mentionedl vcurve is some-1 what smallerl than the other` curve.

The crown plate of thecombustion chamber does not require any reinforcement, such as crown bars or the like, owing'to its shape.

Theinvention may be` also applied to double boilers. In this case the bricking. in of.v

the Water tubes can be dispensed with, the tubes being placed 1n a row or rows in the middle of the combustion chamber, inclosed` between the rear tube plates of .the `two halves of the installation and the bottom of the upper part ofthe boiler, which connects f the two halves. Said bottom .constituting the crown plate of the combstionchamber 1s cylindrically bent downward in the rear tube plate, while the other curve is con- I middle and connected to the rear tube plates by means of curves with a small radius, so that 1n the case of the double boiler also the y construction is sufficiently rigid in itself and crown bars or the like may be omitted.

At the bottom end, the :water tubes are l Y connected to a- 'transverse drum as usual in In known arrangements the afore-men-- this type of boiler, said drum communicating with the interior of the boiler below the grate level, inthe case of a double boiler with the two halves of the installation.

The invention further resides in certain features of construction, arrangement and combination of parts hereinafter more fully described and pointedout'in the appended claims.

2, 4 indicates a boiler shell and issubstantially cylindrical in cross-section. The rear tube plate 1 of the boiler is bent intermediate its length into an S formation and provides a crown plate lying directly over the combustion chamber, as shown at 3. One of the curved ends of the S-shaped crown plate 3 has a greater radius than the other curved end, the end having the greater radius having its convexed portion facing downwardly and the other or smaller end of the plate 3 having its concaved end facing downwardly. Owing to the shape of the crown plate 3, it is not necessary to connect the same in the usual manner by means of crown bars and stay bolts to portions of the'boiler shell 4. The boiler 4 is provided near its bottom with a flue or fire box 9 having disposed thereinthe re bridge 7.

The peculiar formation of the rear tube plate l forms a recess in the rear end of the boiler, as will be clearly seen from ig. 2, which recess provides the combustion chamber 2. Disposed under the crown plate 3 and opposite the -flue or fire box openingI for the combustion chamber 2 formed by the curvature of the rear tube plate 1. These tubes 5 are also curved slightly vertically which increases the strength of the structure and also increases the heating surface of the back wall. The side walls of the combustion chamber 2 may be formed of masonry Yor other suitable ireproof material, as shown'at 2, and the back wall of the combustion chamber 2, formed by the tubes 5, may have a suitable backing of non-heat conducting and fire-proof material, as shown at 2". It will thus be seen from the above that,

the crown plate3 lies directly over the com.-

bustion chamber and that the nest of tubes 5 extending from the transverse boiler 6 lf)orm the back wall of the combustion cham- The tire tubes 10 are disposed in and se'- cured to the boiler 4 above the ire box 9 in ahy suitable or approved manner and have communicationV with the combustion chamber 2 through the rear tube plate l. It will also be seen that a slight curvature in the pipes 5 provides a means for directing the particles of combustion and smoke into the smoke tubes 10, and produces a strong upward circulation of the water through the water tubes to the boiler. l

Connecting the portion of the boiler below the fire box 9 with the water drum 6 is the elbow water connecting tube 8 centrally secured to the water drum 6. Centrally extending in the lower portion of the boiler 4 and forming a continuation of the tube 8 is the tube 11 terminating in the middle of the v boiler and having its inner and free end cut Aat an angle so as to provide an enlarged entrance opening forthe water into the tube. The circulation of water in the boiler is as follows:-F rom the water tube ll, drum 6, through the tubular wall 5, the upper portion of the boiler l and then downwardly through the boiler, contacting with the fire tubes l0 and fire box 9. It will be obvious that the disposition of the tube 1l permits an even circulation of the water since the latter will be equally drawn from the front and rear ends of the boiler, thus preventing a particular circulation in the rear portion of the boiler. I

Having thus described my invention, it is `believed that afull and clear understandingi of the saine will be had, however, certain .changes as to the exact and precise construction may be resorted to that fall within the scope of the appended claims.

What we claim is:

ll. A steam generating device comprising a boiler having the rear wall thereof recessed, a lire box extending through the lower portion of said boiler and communicating with the recess, a transverse water drum supported within the recess andopposite said fire box, a plurality of closely nested, juxtaposed water tubes extending upwardly from said water drum and communicating the latter with the boiler, said nest of tubes forming a solid and continuous rear wall for the boiler and combustion chamber, side walls for said combustion chamber of fire-proof material, a backing of fire-proof material in immediate engagement with said tubes and extending the length of the latter, a fire bridge in said ire box and a bottom wall for said combustion chamber extending between said ire bridge and said watei drum, an elbow water connection between said water drum and the portion of said boiler below said fire box, a tube forming a continuation of said elbow connection and extending within said boiler to a central point thereof, and fire tubes extending through the portion of the boiler above said tire box and communicating with said combustion chamber.

2. Asteam generating device comprising a boiler having the rear wall thereof recessed to form the combustion chamber, a fire-box extending through the lower portion of said boiler and communicating with the recess, a transverse water drum supported within the recess and opposite said fire-box, a plurality of closely nested juxtaposed water tubes extending upwardly from said water drum and communicating the latter with the overlying wall of the boiler, said nest of water tubes forming a solid and continuous rear wall for the boiler and combustion chamber, side walls for the combustion chamber of fire-proof material, and a backing of fire-proof material in immediate names to this specication in the presence of engagement With said tubes and extending the tWo subscribing Witnesses. the length of the latter, said Water tubes be- WOUTER POLDERMN hmmm ing curved outwardly from the boiler 1Iiter- FRIDOI IN HEINRICH LUCHSINGER 5 mediate their ends, for the purpose de- 4 scribed. ANTONINO NAGIEGRUG,

In testimony whereof We have signed our I. I. HELSDON Rox. 

